/*
 * *** BEGIN LICENSE BLOCK *****
 * Version: MPL 1.1/GPL 2.0/LGPL 2.1
 *
 * The contents of this file are subject to the Mozilla Public License Version
 * 1.1 (the "License"); you may not use this file except in compliance with
 * the License. You may obtain a copy of the License at
 * http://www.mozilla.org/MPL/
 *
 * Software distributed under the License is distributed on an "AS IS" basis,
 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
 * for the specific language governing rights and limitations under the
 * License.
 *
 * The Original Code is part of dcm4che, an implementation of DICOM(TM) in
 * Java(TM), hosted at https://github.com/dcm4che.
 *
 * The Initial Developer of the Original Code is
 * J4Care.
 * Portions created by the Initial Developer are Copyright (C) 2015
 * the Initial Developer. All Rights Reserved.
 *
 * Contributor(s):
 * See @authors listed below
 *
 * Alternatively, the contents of this file may be used under the terms of
 * either the GNU General Public License Version 2 or later (the "GPL"), or
 * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
 * in which case the provisions of the GPL or the LGPL are applicable instead
 * of those above. If you wish to allow use of your version of this file only
 * under the terms of either the GPL or the LGPL, and not to allow others to
 * use your version of this file under the terms of the MPL, indicate your
 * decision by deleting the provisions above and replace them with the notice
 * and other provisions required by the GPL or the LGPL. If you do not delete
 * the provisions above, a recipient may use your version of this file under
 * the terms of any one of the MPL, the GPL or the LGPL.
 *
 * *** END LICENSE BLOCK *****
 */

package org.dcm4chee.arc.validation.constraints;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.lang.reflect.Field;
import java.security.AccessController;
import java.security.PrivilegedActionException;
import java.security.PrivilegedExceptionAction;

/**
 * @author Gunter Zeilinger <gunterze@gmail.com>
 * @since Aug 2015
 */
class FieldValue {
    private final static Logger log = LoggerFactory.getLogger(FieldValue.class);
    private final Object obj;
    private final String name;

    public FieldValue(Object obj, String name) {
        this.obj = obj;
        this.name = name;
    }

    public Object get() throws Exception {
        try {
            return AccessController.doPrivileged(new PrivilegedExceptionAction<Object>() {
                @Override
                public Object run() throws Exception {
                    Field field = obj.getClass().getDeclaredField(name);
                    field.setAccessible(true);
                    return field.get(obj);
                }
            });
        } catch (PrivilegedActionException e) {
            throw e.getException();
        }
    }

    public static Logger log() {
        return log;
    }
}
